Mobile device, and method for releasing lock of the mobile device via handwriting recognition

ABSTRACT

A method, and a mobile device adapted thereto, verifies a user and executes applications via handwriting recognition. The method of controlling a mobile device includes entering a lock state, detecting a user&#39;s input, verifying a user based on the input and searching for an instruction corresponding to the input, and performing at least one of maintaining or releasing the lock state and which performs an operation corresponding to the instruction, based on user verification result and the instruction search result.

PRIORITY

This application is a continuation application of U.S. patentapplication Ser. No. 15/388,878, which was filed on Dec. 22, 2016, whichis a continuation application of U.S. patent application Ser. No.13/787,088, which was filed on Mar. 6, 2013, now U.S. Pat. No. 9,572,028issued on Feb. 14, 2017 and which claims priority under 35 U.S.C. §119(a) to a Korean patent application filed on Aug. 1, 2012 in theKorean Intellectual Property Office and assigned Serial No.10-2012-0084326, the contents of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates generally to a method for verifying amobile device user and executing applications, via handwritingrecognition, and to a mobile device adapted to the method.

2. Description of the Related Art

The importance of protecting personal information in mobile devices hassignificantly increased in relation to the increase in the number ofpeople who use touch screen-based mobile devices, such as smart phones.A lock mode is a conventional method of protecting personal informationin mobile devices. For example, if a user needs to operate his/hermobile device, set in a conventional lock mode state, he/she must firstrelease the lock in order to execute a corresponding application in themobile device.

FIG. 1 illustrates a conventional method requiring a mobile device userto input a specific pattern to the mobile device in order to release thelock state. When the mobile device verifies the user's input pattern asa correct pattern as shown in the left diagram of FIG. 1, the mobiledevice displays an idle screen. If the user selects an application, suchas a call application, as shown in the middle diagram, the mobile deviceexecutes the application and displays the corresponding screen as shownin the right diagram.

However, conventional methods inconveniently require a number of userinput operations to operate a mobile device from a step for releasingthe lock state to a step for executing an application. In addition,since conventional lock patterns are set by the use of nine pointsarranged in matrix form on the screen, the configuration results in arelatively simple combination producing a low level of security of thelock. This results in a user's dissatisfaction with the lock state ofthe mobile device.

SUMMARY OF THE INVENTION

The present invention has been made in view of the above problems, andprovides a method that can release a lock state of a mobile device andexecute corresponding functions, via handwriting recognition. Thepresent invention further provides a mobile device adapted to themethod.

In accordance with an embodiment of the present invention, provided is amethod which controls a mobile device, including entering a lock state,detecting an input in the lock state, verifying a user based on theinput and searching for an instruction corresponding to the input, andperforming at least one of maintaining or releasing the lock state basedon the verification result and which performs an operation correspondingto the instruction based on the instruction search result.

In accordance with another embodiment of the present invention, providedis a mobile device, including an input unit which detects an input, adisplay unit for displaying information, and a controller which controlsthe display unit to display a lock screen when entering a lock state,which verifies, when the input is detected via the input unit, a userbased on the input and for searching for an instruction corresponding tothe input at the same time, and which performs at least one ofmaintaining or releasing the lock state based on the verification resultand which performs an operation corresponding to the instruction basedon the instruction search result.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and advantages of the invention will become more apparentfrom the following detailed description viewed in conjunction with theaccompanying drawings, in which:

FIG. 1 illustrates a conventional method of controlling a mobile device;

FIG. 2 illustrates a schematic block diagram of a mobile deviceaccording to an embodiment of the invention;

FIG. 3 illustrates a configuration of the input unit according to anembodiment of the invention;

FIG. 4 illustrates a method for registering user verificationinformation according to an embodiment of the invention;

FIG. 5 illustrates a text for verification input to an input unitaccording to an embodiment of the invention;

FIG. 6 illustrates another text for verification input to an input unitaccording to an embodiment of the invention;

FIG. 7 shows an example of verification information according to anembodiment of the invention;

FIG. 8 illustrates a method of controlling a mobile device according toan embodiment of the invention;

FIG. 9 illustrates a method of verifying a user of a mobile deviceaccording to an embodiment of the invention;

FIG. 10 is an instruction table according to an embodiment of theinvention;

FIG. 11 illustrates an example where the lock state of a mobile deviceis maintained;

FIG. 12 illustrates an example where the lock state of a mobile deviceis released and the mobile device executes an application; and

FIG. 13 illustrates an example where the lock state of a mobile deviceis released and an idle screen is displayed.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE PRESENT INVENTION

Embodiments of the present invention are described in detail withreference to the accompanying drawings. The same reference numbers areused throughout the drawings to refer to the same or like parts.Detailed descriptions of well-known functions and structuresincorporated herein may be omitted to avoid obscuring the subject matterof the present invention.

The mobile device according to the invention can be applied to smartphones, portable terminals, mobile communication terminals, PersonalDigital Assistants (PDAs), Portable Multimedia Players (PMPs),computers, laptop computers, note pad devices, Wibro terminals, tabletPersonal Computers (PCs), smart Televisions (TVs), and smartrefrigerators for example.

The terms or words described in the present description and the claimsshould not be limited by a general or dictionary meaning, and insteadshould be understood as having the meaning conveyed in the description.One skilled in the art will understand that the embodiments disclosed inthe description and configurations illustrated in the drawings are onlyexamples, and there may be various modifications, alterations, andequivalents thereof to replace the embodiments at the time of filingthis application.

As used herein, the singular forms “a,” “an” and “the” are intended toinclude the plural forms as well, unless expressly stated otherwise. Itwill be further understood that the terms “includes,” “comprises,”“including” and/or “comprising,” when used in this specification,specify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof.

FIG. 2 illustrates a block diagram of a mobile device according to anembodiment of the present invention.

Referring to FIG. 2, the mobile device 100 includes an input unit 110, acontroller 120, a storage unit 130 and a display unit 140.

The input unit 110 creates operation signals according to the user'sinputs. The input unit 110 includes a touch sensor 111, a proximitysensor 112 and an electromagnetic sensor 113.

The touch sensor 111 detects the user's touch inputs. The touch sensor111 may include a touch film, a touch sheet, and a touch pad, forexample. The touch sensor 111 detects a touch input and transfers thedetected touch signal to the controller 120. The controller 120 analyzesthe touch signal and executes the corresponding function. Theinformation corresponding to the detected touch signal may be displayedon the display unit 140. The touch sensor 111 receives operation signalscreated when the user inputs touches via a variety of touch means. Thetouch sensor 111 receives an operation signal from a user's body (suchas a finger). According to the types of implementations, the touchsensor 111 detects a direct touch or a proximity input within a certainrange of distance.

The proximity sensor 112 detects, for example, a presence, an approach,a motion, a direction, a speed, or a shape of a nearby object in thedetection surface of the input unit 110, via the electromagnetic fieldintensity, without any mechanical contact. The proximity sensor 112 is,for example, a transmission photoelectric type, a direct reflectivephotoelectric type, a mirror photoelectric type, a high frequencyoscillation type, a capacitance sensor, a magnetic type, or an infraredtype.

The electromagnetic sensor 113 detects a touch or proximity inputaccording to the change in electromagnetic field intensity. Theelectromagnetic sensor 113 may be an Electro Magnetic Resonance (EMR)type of input pad. The electromagnetic sensor 113 includes coilsinducing magnetic fields, and detects the approach of an objectincluding a resonant circuit that creates the change in magnetic fieldenergy. The electromagnetic sensor 113 detects an input via an objectincluding a resonant circuit, such as a stylus pen. The electromagneticsensor 113 can also detect a proximity input or hovering input to themobile device 100 as well as an input to the mobile device 100 via adirect touch.

FIG. 3 illustrates a configuration of the input unit according to anembodiment of the present invention. Referring to FIG. 3, the input unit110 includes first 110 a and second 110 b input pads forming layers. Thefirst 110 a and second 110 b input pads may be implemented with apressure pad, a touch pad, including a proximity sensor 112 and a touchsensor 111, EMR pad, or an electromagnetic pad with an electromagneticsensor 113. The first 110 a and second 110 b input pads may beimplemented with different types of input means with which to detect theinputs. For example, the first input pad 110 a, detects a touch inputfrom a user's body when implemented with a touch pad. Likewise, if thesecond input pad 110 b detects an input by a stylus pen when implementedwith an EMR pad.

The input unit 110 is configured to form a layer with the display unit140. The first input pad 110 a and second 110 b input pad are placedunder the display unit 140, and detect inputs created, via icons, menus,buttons. displayed on the display unit 140, which is a display panel ora Touch Screen Panel (TSP) combined with an input pad. The controller120 can identify the type of input means according to whether the inputsignal is detected via the first 110 a or second 110 b input pad.

The configuration combining the input unit 110 with the display unit140, as shown in FIG. 3, is an example. Therefore, it should beunderstood that there are many modifications according to the number andtype of input pads of the input unit 110 and the arrangement of thedisplay unit 140 and the input pad forming upper and lower layers,according to technology employed in the mobile device 100.

The input unit 110 detects a user's inputs for entering a lock state ora lock state release. The input unit 110 detects a user's inputs forstoring information to control functions of the mobile device 100 or thelock state release. For example, the input unit 110 detects a user'sinputs for registering user verification information, and inputs forinstructions, signature or text used for user verification.

The controller 120 controls respective components in the mobile device100, thereby controlling the entire operation of the mobile device 100.For example, the controller 120 determines whether the lock state of themobile device 100 is released based on input detected via the input unit110, and whether to operate an application.

The controller 120 includes a verification module 121 and a characterrecognition module 122.

The verification module 121 performs a user verification procedure byextracting an input feature from the detected input and comparing theextracted input feature with that of previously stored user verificationinformation. The verification module 121 performs a comparison processas to the identity/similarity/difference between the input properties,by using a variety of algorithms, such as a character stream comparisonalgorithm, including Brute Force, Knuth-Morris-Pratt, Boyer-Moore,Shift-Or, or an image comparison algorithm such as a neural networkalgorithm or a bitmap algorithm.

The verification module 121 determines whether the verification issuccessful according to the comparison result. The verification module121 calculates the degree of similarity based on the comparison result.If the degree of similarity is greater than or equal to a presetthreshold, the verification module 121 concludes that the verificationis successful. If the degree of similarity is less than the presetthreshold, the verification module 121 concludes that the verificationis unsuccessful.

The character recognition module 122 extracts one or more characterssuch as letters, numbers, special characters, symbols, and space, froman input. The character recognition module 122 can recognize and extractone or more characters by using pattern matching or structure analysis,for example.

The controller 120 performs a user verification procedure via theverification module 121, for an input detected in the lock state. Inaddition, the controller 120 can recognize text having the one or morecharacters extracted by the character recognition module 122, and searchfor instructions corresponding to the recognized text.

The controller 120 maintains or releases a lock state of the mobiledevice 100 according to the user verification result or executes afunction according to the instruction search result.

The storage unit 130 stores programs or instructions related to theoperations of the mobile device 100. The controller 120 executes theprograms or processes the instructions.

The storage unit 130 may be implemented with various types of storagemedia, such as flash memory, hard disk, multimedia card micro memory,memory card, Random Access Memory (RAM), Static Random Access Memory(SRAM), Read-Only Memory (ROM), Electrically Erase ProgrammableRead-Only Memory (EEPROM), Programmable Read-Only Memory (PROM),magnetic memory, magnetic disk, or optical disk.

In an embodiment of the invention, the storage unit 130 stores userverification information with an input feature and information regardinga type of input means, as well as information regarding operationscorresponding to instructions in an instruction table.

The display unit 140 displays information, processed in the mobiledevice 100. For example, the display unit 140 may display User Interface(UI) or Graphic User Interface (GUI) related to the control of functionsof the mobile device 100.

The display unit 140 may be implemented with a flat display panel, suchas a Liquid Crystal Display (LCD), a Thin Film Transistor-Liquid CrystalDisplay (TFT LCD), Organic Light Emitting Diodes (OLEDs), a flexibledisplay, or a three-dimensional (3D) display.

The display unit 140 may be configured with a touch screen and touchsensors serving as the input unit 110, where the touch screen and touchsensors form layers. The display unit 140 may be implemented with adisplay panel combined with touch sensors, such as TSP. That is, thedisplay unit 140 serving as a touch screen may also serve to performfunctions of an input device.

In an embodiment of the invention, the display unit 140 can display auser's input gesture. The display unit 140 can also display a lock statescreen, an idle screen or an application execution screen, under thecontrol of the controller 120.

It should be understood that the mobile device 100 may be modified toremove part of the components shown in FIG. 2 or may further includeother components (not shown), showing the features of the invention.

FIG. 4 illustrates a method for registering user verificationinformation according to an embodiment of the present invention.

The mobile device 100 detects an input at step 210.

For example, the mobile device 100 detects an input for registering userverification information while executing the application for registeringuser verification information, a setting program, or a service program.User verification information serves to determine, when the mobiledevice 100 operates in a lock state, whether a user, who has applied aninput for releasing the lock state to the mobile device 100, is a validuser. User verification information is created via valid user inputs andregistered in the mobile device 100.

The input for registering user verification information may beimplemented with an operation/motion forming/drawing a certain shape,such as a letter, a number, or a special symbol. The input may be a wordto identify a user, such as a name (‘Brown,’ ‘John,’ etc.), sex, or anickname. The input may also be a word representing an application,program, or service, such as ‘call,’ ‘memo,’ or ‘map’.

The input for registering user verification information may be input tothe mobile device 100 via a specific input means, such as a user'sfinger or a stylus pen. The types of inputs may be a touch input and aproximity input.

As shown in FIG. 5, the mobile device 100 detects an input 10 forregistering user verification information. The input 10 may be a touchinput by a stylus pen or a word corresponding to the mobile deviceuser's name ‘Brown.’ Alternatively, as shown in FIG. 6, the mobiledevice 100 detects an input representing a call application ‘call Mom.’

Returning to FIG. 4, when detecting an input at step 210, the mobiledevice 100 extracts an input feature at step 220, which includes atleast one of an input means, a shape of an inputting gesture, and aspeed of an inputting gesture, for example.

The mobile device 100 can identify an input means, such as a user'sfinger, hand, or a stylus pen, according to a detected input.Alternatively, the mobile device 100 may include a number of sensors todetect various types of input means. In that case, the mobile device 100can identify an input means via the corresponding sensor that detectsthe input. The mobile device 100 may include a number of sensorsconfigured in a pad, such as a touch pad, an EMR pad or a TSP.

The mobile device 100 detects types of input means based on areas towhich the input means is applied. For example, if the mobile device 100ascertains that a detected area to which an input means is applied isgreater than a threshold value, the mobile device 100 identifies theinput means as a user's finger. If a detected area to which an inputmeans is applied is less than or equal to a threshold value, the mobiledevice 100 identifies the input means as a stylus pen.

The mobile device 100 may extract two- or three-dimensional coordinatesof a detected input during a preset period. The mobile device 100 canextract the coordinates, on a basis of a point where an input started,as the original point. Since the mobile device 100 extracts coordinatesof inputs, on the basis of a relative point where an input started, andnot an absolute point, the mobile device 100 can extract a shape of aninput operation, irrespective of the location/point where the input isdetected.

The mobile device 100 can calculate a movement distance (based on ameasurement of pixels, mm, or cm.) of an input operation input during apreset period, based on the extracted coordinates, and then compute thespeed of the input operation according to the period. The mobile device100 can compute the average speed or the speed deviation for the entireinput operation.

After extracting the input feature at step 220, the mobile device 100creates user verification information at step 230 based on the extractedinput feature. As shown in FIG. 7, user verification information mayinclude an input feature, such as input means, input shape, averagespeed, and speed deviation.

The input shape corresponds to data representing an image created whenan input operation forms a track or data to be shown as coordinatesextracted according to a preset period from an input. The coordinatesextracted from an input may refer to coordinates of a location relativeto a point where the input started, not an absolute point where theinput is made. Therefore, the coordinates of an input may represent ashape formed by an input, on the basis of a point where the inputstarts, irrespective of an absolute point where the input is made.

The average speed refers to a value that is calculated via thecoordinates extracted from the inputs. Speed according to periods can becalculated via a distance between coordinates extracted at a certainperiod. An average speed can be calculated by averaging speeds accordingto periods. The speed deviation refers to respective periods, based onthe average speed.

As shown in FIG. 5, the mobile device 100 can extract an input feature,on the basis of the coordinates extracted from an input 10, ‘Brown.’ Themobile device 100 can calculate speeds according to periods, bydetecting the number of pixels between coordinates extracted duringevery preset period, 1 ms.

The mobile device 100 averages speeds according to periods, andcalculates the average speed for inputs by a stylus pen as shown in FIG.7, thereby creating user verification information including thecalculation result of 40 pixels/ms. Alternatively, as shown in FIG. 5,the mobile device 100 can extract the input 10, ‘Brown,’ as image data,thereby creating user verification information including the extractedimage data. In that case, the mobile device 100 may create userverification information by extracting coordinates from the input 10,‘Brown,’ every 1 ms.

Returning to FIG. 4, after creating user verification information atstep 230, the mobile device 100 stores the user verification informationin the storage unit 130 at step 240.

The user verification information may include the extracted inputfeature.

The mobile device 100 may also store a threshold value and a weight inorder to determine the similarity with respect to user verificationinformation.

The weight refers to an index to set the degree of sensitivity of theinput feature, large or small, when the mobile device 100 determines thesimilarity between the stored user verification information and a user'sinput in order to release a lock state of the mobile device 100. Thatis, the weight may be a ratio of respective input features to the totalsimilarity. The weight may be set as a value to minimize the Equal ErrorRate (EER) performance in an input detection experiment. Alternatively,the weight may be set as values according to types of input means,respectively.

The threshold value refers to a minimum value of the similarity toverify a mobile device user's identity. That is, the threshold value isa minimum value of the similarity to conclude that a user's input torelease a lock state of the mobile device 100 is identical to, orsimilar to, the stored user verification information. The thresholdvalue may be set with different values, according to types of inputmeans, based on weights acquired via the input detection experiments.

The mobile device 100 determines a weight and a threshold valuecorresponding to an input means, and stores them associated therewith.

The mobile device 100 extracts characters from a user's input and storesinstructions corresponding to the extracted characters and an operationcorresponding to the instructions.

The mobile device 100 can extract letters, numbers, special characters,symbols, and space from the input. The mobile device 100 can extract thecharacters via pattern matching or structure analysis, for example. Themobile device 100 can extract part or all of the characters that theuser input.

The mobile device 100 can recognize texts from the extracted part or allof the characters, and can create instructions corresponding to therecognized text. Examples of the instructions are related to a callingfunction, an emailing function, a messaging function, a note function, amap function, and a function for opening photograph/video files.

For example, as shown in FIG. 6, the mobile device 100 may extract thecharacters ‘c’, ‘a’, ‘I’, ‘I’, ‘ ’, ‘M’, ‘o’, ‘m’, and recognize thetext ‘call Mom’. The mobile device 100 may create an instruction forplacing a call corresponding to the text ‘call’ or ‘call Mom’.

The mobile device 100 can set an operation, associated with the createdinstruction. For example, the mobile device 100 can store the createdinstruction ‘call Mom,’ associated with an operation for placing a callto the phone number that is stored with the title ‘Mom’ in the contactlist. Alternatively, the mobile device 100 can store the createdinstruction ‘call,’ associated with an operation for placing a call to aphone number corresponding to a text extracted before or after ‘call.’

The information, created by an instruction and an operation associatedtherewith, is referred to as an instruction table, and will be describedin detail later referring to FIG. 10.

The mobile device 100 receives user input corresponding to anapplication, a program, a service or a function, and executes thecorresponding operation. To this end, the mobile device 100 detects theuser's inputs and stores the letters extracted from the inputs,associated with the corresponding operations.

After storing user verification information at step 240, the mobiledevice 100 determines whether the input termination is made at step 250.

The determination whether the input termination has been made is basedon whether the number of times of detecting input for registering userverification information matches a preset number.

Although the user may create the same input as the stored userverification information, input features of user inputs may differ fromeach other each time that they are input. Therefore, the mobile device100 detects inputs to register user verification information by a presetnumber of times, and extends the range of identity/similarity for auser's input. In addition, the mobile device 100 extracts input featuresfor a preset number of inputs, respectively, and then the deviation forthe respective input features, based on the extracted input features.For example, the mobile device 100 can extract the deviation of a numberof speeds extracted from the corresponding input numbers, respectively.

When the number of times of detecting input for registering userverification information matches a preset number, the mobile device 100concludes that the input is terminated. Alternatively, if the userinputs a request for terminating the registration, the mobile device 100concludes that the input is terminated. If the mobile device 100 detectsinputs corresponding to a preset number of input operations, the mobiledevice 100 displays the remaining number of times, such as ‘2 more timesare required,’ labeled by reference number 20 as shown in FIG. 5.

If the mobile device 100 detects inputs by a preset number of inputoperations, the mobile device 100 can compare the input features of theinputs with each other. If the mobile device 100 ascertains that thereis a relatively large difference between the input features of theinputs, the mobile device 100 can display a message showing that theinput is unsuccessful. For example, if the user inputs ‘Brown,’ at thefirst input operation and then ‘John,’ at the second input operation,the mobile device 100 ascertains that ‘Brown’ and ‘John’ differ fromeach other in terms of input feature and thus cannot create the userverification information. In that case, the mobile device 100 informsthe user that the input is unsuccessful and waits for a user's input.

If the mobile device 100 ascertains that the input termination is notmade at step 250, the mobile device 100 returns to and detects a user'sinput at step 210.

FIG. 8 illustrates a method of controlling a mobile device according toan embodiment of the present invention. Referring to FIG. 8, the mobiledevice 100 enters a lock state at step 310.

Particularly, the mobile device 100 enters a lock state, operating in alock mode, thereby locking a function for opening information regardinga memo to set a lock, an image, a video, a contact, and a schedule, anda function for purchasing paid information, an application, or contents.When the mobile device 100 enters a lock state a lock screen isdisplayed.

After entering a lock state at step 310, the mobile device 100 detectsan input by an input operation at step 320.

The input may be implemented with an operation/motion forming a shape,such as a letter, a number, or a special symbol. For example, the inputmay be a word to identify a user, such as a name (‘Brown,’ ‘John,’etc.), sex, or a nickname. The input may also be a word representing anapplication, program or service, such as ‘call,’ ‘memo,’ and ‘map’.

The input may be created via a specific input means, such as a user'sfinger, hand, and a stylus pen. The types of inputs may be a touch inputor a proximity input.

For example, the mobile device 100 detects an input 10 by a stylus pen,‘Brown,’ as shown in FIG. 5, or ‘call Mom,’ as shown in FIG. 6, in alock state.

When detecting the input at step 320, the mobile device 100 performs auser verification procedure and searches for an instructioncorresponding to the input at step 330. The user verification procedureand the instruction search procedure may be simultaneously performedaccording to the scheduling process of the mobile device 100.

When detecting the input at step 320, the mobile device 100 performs auser verification procedure, which is described in detail referring toFIG. 9.

The mobile device 100 extracts the input feature at step 331, whichincludes at least one of a type of input means, a shape of an inputtinggesture, and a speed of an inputting gesture, for example.

The mobile device 100 identifies an input means, such as a user's fingeror a stylus pen, according to a detected input. Alternatively, themobile device 100 may include a number of sensors to detect varioustypes of input means. In that case, the mobile device 100 can identifyan input means via the corresponding sensor that detects the input. Themobile device 100 may include a number of sensors configured in a pad,such as a touch pad, an EMR pad, and a TSP.

The mobile device 100 detects types of input means based on areas towhich the input means is applied. For example, if the mobile device 100ascertains that a detected area to which an input means is applied isgreater than a threshold value, the mobile device 100 identifies theinput means as a user's finger. If a detected area to which an inputmeans is applied is less than or equal to a threshold value, the mobiledevice 100 identifies the input means as a stylus pen.

The mobile device 100 may extract two- or three-dimensional coordinatesof a detected input during a preset period. The mobile device 100 canextract the coordinates, on a basis of a point where an input started,as the original point. Since the mobile device 100 extracts coordinatesof inputs, on the basis of a relative point where an input started, andnot an absolute point, the mobile device 100 can extract a shape of aninput operation, irrespective of the location/point where the input isdetected.

The mobile device 100 can calculate a movement distance (based on ameasurement of pixels, mm, or cm, for example.) of an input operationinput during a preset period, based on the extracted coordinates, andthen compute the speed of the input operation according to the period.The mobile device 100 can compute the average speed or the speeddeviation for the entire input operation.

The mobile device 100 then compares the extracted input feature with theuser verification information at step 332.

The user verification information may be previously stored in the mobiledevice 100 when it is manufactured or may be stored via the userverification information storing method according to the presentinvention.

The mobile device 100 performs a comparison process as to theidentity/similarity/difference between the input properties, by using avariety of algorithms, such as a character stream comparison algorithm,such as Brute Force, Knuth-Morris-Pratt, Boyer-Moore, Shift-Or, or animage comparison algorithm such as a neural network algorithm, or abitmap algorithm.

The mobile device 100 performs the comparison between the input featuresextracted from the inputs of the input means. The mobile device 100 cancompare the extracted input feature with one of the input features ofuser verification information, corresponding to the input means.

The mobile device 100 computes the similarity at step 333.

The mobile device 100 can convert the similarity between the detectedinput and the stored, user verification information into numerals, basedon the comparison result of the input features. The mobile device 100calculates the similarities according to the input features and sums thesimilarities, thereby acquiring the total similarity.

The mobile device 100 can set weights of the similarities according tothe input features. The weight refers to an index to set the degree ofsensitivity of the input feature, large or small, when the mobile device100 determines the similarity between the stored, user verificationinformation and a user's input in order to release a lock state of themobile device 100. That is, the weight may be a ratio of respectiveinput features to the total similarity. The weight may be set as a valueto minimize the EER performance in an input detection experiment.Alternatively, the weight may be set as values according to types ofinput means, respectively.

The mobile device 100 can calculate the total similarity, based on thesimilarities according to input features and the weights correspondingto input means. For example, if the number of input features is n, themobile device 100 can calculate the total similarity, based on thesimilarities according to input features, Similarity₁, Similarity₂, . .. , Similarity_(n), and the weights for the input features, f₁, f₂, . .. , f_(n). The total similarity is expressed as in the followingEquation (1).

Total similarity=f ₁×(Similarity₁)+f ₂×(Similarity₂)+ . . . f_(n)×(Similarity_(n))  (1)

The mobile device 100 determines whether the total similarity is greaterthan or equal to a threshold value at step 334.

The threshold value refers to a minimum value of the similarity toverify a mobile device user's identity. That is, the threshold value isa minimum value of the similarity to conclude that a user's input torelease a lock state of the mobile device 100 is identical to or similarto the stored, user verification information. The threshold value may beset with different values, according to types of input means, based onweights acquired via the input detection experiments.

If the mobile device 100 ascertains that total similarity is greaterthan or equal to a threshold value at step 334, the mobile device 100concludes that the verification is successful at step 335.

If the mobile device 100 ascertains that total similarity is less thanthe threshold value at step 334, the mobile device 100 concludes thatthe verification is unsuccessful at step 336.

Referring back to the procedure as shown in FIG. 8, when the mobiledevice 100 detects the input at step 320, the mobile device 100 alsosearches for an instruction corresponding to the input.

The mobile device 100 can extract characters from the input, such asletters, numbers, special characters, symbols, or space. The mobiledevice 100 can recognize and extract characters by using patternmatching and structure analysis, for example. The mobile device 100 canextract part or all of the characters from the input, and can recognizetexts including the extracted characters.

The mobile device 100 can search for an instruction corresponding topart or all of the extracted characters, and can store instructions inan instruction table as shown in FIG. 10. The instruction table includesa number of fields, inputs, texts extracted from an input, applications,programs or services corresponding to a text, and detailed description.

The input field includes an input that refers to information created bycapturing a detected input or information regarding coordinatesextracted from an input. The input may be information regarding a shapeof a detected input, and may refer to a specific function of the mobiledevice 100, such as a track of an ‘email,’ ‘browser,’ ‘gallery,’ ‘map,’or ‘call,’ shape.

The text field includes texts having part or all of extracted charactersfrom an input. The text may be an instruction for executing an operationcorresponding to a specific function. Examples of the text extractedfrom an input are ‘email,’ ‘browser,’ ‘gallery,’ ‘map,’ and ‘call’.

The field of application, program or service corresponding to a textincludes applications, programs or services corresponding to a textextracted from an input, i.e., an instruction. An example of theapplication, program or service corresponding to a text is informationregarding a name of an application for executing a web browsercorresponding to an instruction ‘browser,’ a location of the executedfile, and a download path.

The field of detailed description includes information for executing anoperation corresponding to an instruction, and a method for acquiringcorresponding information. Examples of the detailed description may beinformation for transmitting an email corresponding to an instruction‘email,’ such as information regarding a sender and a receiver, andinformation regarding a method for acquiring information regarding asender and a receiver, based on an extracted text and the instruction.

The detailed description may also be a Uniform Resource Locator (URL) ofa website, required when a web browser application is executed by aninstruction ‘browser’, and information regarding a method for acquiringthe URL, based on the extracted text and instruction.

The instruction table may be created via a user's inputs, such thatinstructions are associated with applications, programs, or services.

The mobile device 100 searches for an instruction corresponding torecognized text having the extracted characters from the instructiontable. The mobile device 100 may search for an instructionidentical/similar to part or all of the text.

The mobile device 100 can acquire information regarding an operationcorresponding to an instruction from the instruction table.

The mobile device 100 can acquire information regarding an applicationin the application field or information regarding an operationcorresponding to an instruction in the detailed description field fromthe instruction table.

The mobile device 100 maintains or releases the lock state according toa result of a user's verification or executes an operation correspondingto an instruction according to the instruction search result.

Referring back to FIG. 8, the mobile device 100 determines whether userverification is successful according to user verification procedure atstep 340.

If the mobile device 100 ascertains that user verification isunsuccessful at step 340, the lock state is maintained at step 350. Inaddition, as shown in FIG. 11, the mobile device 100 may output a text,an image, an icon, a haptic effect, or a sound effect, indicating thatthe verification is unsuccessful. In that case, the mobile device 100may re-detect an input for a user verification procedure at step 310.Since user verification is unsuccessful, the mobile device 100 does notallow the user to execute any control operation for a preset period oftime or to apply a new input operation thereto. Alternatively, if themobile device 100 detects that the number of verification attemptsexceeds a present value, the user is not allowed to execute any controloperation for a preset period of time or to apply a new input operationthereto.

If the mobile device 100 ascertains that user verification is successfulat step 340, the lock state is released. In that case, the mobile device100 executes an operation corresponding to an instruction or displays anidle screen or a screen of the currently executed application. Theinstruction is related to the execution of a function such as a calling,an emailing, a messaging, or a note function, an executing of anapplication related to a map, or an opening of photograph/video files.

As such, if the mobile device 100 ascertains that user verification issuccessful at step 340, the mobile device 100 determines whether aninstruction corresponding to an input exists according to theinstruction search procedure at step 360.

If the mobile device 100 ascertains that an instruction corresponding toan input exists at step 360, the mobile device 100 acquires informationregarding an operation corresponding to the instruction and executes theoperation at step 370. The instruction is related to the operation foran application, a program, or a service. For example, as shown in FIG.12, the mobile device 100 places a call to the phone numbercorresponding to a title ‘Mom’ in the contact list, according to the‘call Mom’ instruction. Alternatively, the mobile device 100 places acall to the phone number corresponding to a text extracted with ‘call’in the contact list, according to the ‘call’ instruction.

If the mobile device 100 does not include an application, a program, ora service corresponding to the instruction, an installation file basedon the acquired information may be downloaded. After installing thedownloaded files, the mobile device 100 executes the application and/orthe program, or provides the service.

If the mobile device 100 ascertains that an instruction corresponding toan input does not exist at step 360, the lock state is released at step380. In that case, the mobile device 100 displays an idle screen or ascreen of the currently executed application. For example, as shown inFIG. 13, the mobile device 100 may display an idle screen that showswidgets, icons, short-cut keys, or state information, on a backgroundimage.

As described above, the method according to the present invention canrecognize a user's handwriting, input to a mobile device in a lock stateand release the lock state of the mobile device, so that the user canintuitively and easily execute functions by corresponding instructions.

Since the method according to the present invention determines whetherto release a lock sate of a mobile device via the user's input text, thelevel of security in the mobile device is significantly increased,allowing the user to easily and more confidently control the functionsof the mobile device.

Although embodiments of the present invention have been described indetail hereinabove, it should be understood that many variations andmodifications of the basic inventive concept herein described, which maybe apparent to those skilled in the art, will still fall within thespirit and scope of the embodiments of the present invention as definedin the appended claims.

What is claimed is:
 1. A method of controlling an electronic devicecomprising: displaying a lock screen user interface on a touch sensitivedisplay of the electronic device, wherein the touch sensitive display iscapable of detecting contact with a user body; detecting a user inputthrough the touch sensitive display while displaying the lock screenuser interface; displaying a drawing on the lock screen user interface,wherein the drawing comprises one or more marks corresponding to theuser input; determining whether the user input is a predefined input;and replacing, when the user input is the predefined input, the lockscreen user interface with an execution screen of an application,wherein the application corresponds to the user input.
 2. The method ofclaim 1, wherein replacing, when the user input is the predefined input,the lock screen user interface with the execution screen of theapplication comprises: bypassing an unlock user interface, in responseto a determination that the user input is the predefined input; anddisplaying the execution screen of the application.
 3. The method ofclaim 1, wherein determining whether the user input is the predefinedinput comprises: verifying a user based on the detected user inputthrough the touch sensitive display; and concluding that theverification of the user is successful based on a result of theverification of the user result.
 4. The method of claim 3, whereinverifying the user based on the detected user input through the touchsensitive display comprises: extracting an input feature of the detecteduser input through the touch sensitive display; comparing the inputfeature with predefined verification information; and determiningwhether a verification of user is successful based on a result of thecomparison result.
 5. The method of claim 4, wherein determining whetherthe verification of user is successful based on the result of thecomparison result comprises: calculating a similarity between the inputfeature with the predefined verification information; and concludingthat the verification of user is successful when the similarity isgreater than or equal to a threshold value or that the user verificationis unsuccessful when the similarity is less than the threshold value. 6.The method of claim 4, wherein determining whether the user input is thepredefined input further comprises: searching for an instructioncorresponding to the user input through the touch sensitive display; andascertaining whether information related to the execution for theapplication exists.
 7. The method of claim 6, wherein determiningwhether the user input is the predefined input further comprises: whenthe verification of the user is successful and ascertaining whether theinformation related to the execution for the application exists,concluding that the user input is a predefined input.
 8. The method ofclaim 7, wherein further comprising: when the verification of the useris successful and ascertaining whether the information related to theexecution for the application does not exist, releasing the lock screenuser interface; and displaying an idle screen or a screen of apreviously executed application.
 9. An electronic device comprising: adisplay; at least one processor; and a memory configured to storeinstructions to cause the processor to: display a lock screen userinterface on a touch sensitive display of the electronic device, whereinthe touch sensitive display is capable of detecting a contact with auser body; detect a user input through the touch sensitive display whiledisplaying the lock screen user interface; display a drawing on the lockscreen user interface, wherein the drawing comprises one or more markscorresponding to the user input; determine whether the user input is apredefined input; and replace, when the user input is the predefinedinput, the lock screen user interface with an execution screen of anapplication, wherein the application corresponds to the user input. 10.The electronic device of claim 9, wherein the processor is furtherconfigured to: bypass an unlock user interface, in response to adetermination that the user input is the predefined input; and displaythe execution screen of the application.
 11. The electronic device ofclaim 9, wherein the processor is further configured to: verify a userbased on the detected user input through the touch sensitive display;and conclude that the verification of user is successful based on aresult of the verification of the user result.
 12. The electronic deviceof claim 11, wherein the processor is further configured to: extract aninput feature of the detected user input through the touch sensitivedisplay; compare the input feature with predefined verificationinformation; and determine whether a verification of the user issuccessful based on a result of the comparison result.
 13. Theelectronic device of claim 11, wherein the processor is furtherconfigured to: calculate a similarity between the input feature with thepredefined verification information; and conclude that the verificationof the user is successful when the similarity is greater than or equalto a threshold value or that the user verification is unsuccessful whenthe similarity is less than the threshold value.
 14. The electronicdevice of claim 12, wherein the processor is further configured to:search for an instruction corresponding to the user input through thetouch sensitive display; and ascertain whether information related tothe execution for the application exists.
 15. The electronic device ofclaim 14, wherein the processor is further configured to: when theverification of the user is successful and ascertaining whether theinformation related to the execution for the application exists,conclude that the user input is the predefined input.
 16. The electronicdevice of claim 15, wherein the processor is further configured to: whenthe verification of the user is successful and ascertaining whether theinformation related to the execution for the application does not exist,release the lock screen user interface; and display an idle screen or ascreen of a previously executed application.
 17. A non-transitorycomputer-readable medium having stored thereon instructions that, whenexecuted by at least one processor of an electronic device, causes theelectronic device to perform a method, the method comprising: displayinga lock screen user interface on a touch sensitive display of theelectronic device, wherein the touch sensitive display is capable ofdetecting contact with a user body; detecting a user input through thetouch sensitive display while displaying the lock screen user interface;displaying a drawing on the lock screen user interface, wherein thedrawing comprises one or more marks corresponding to the user input;determining whether the user input is a predefined input; and replacing,when the user input is the predefined input, the lock screen userinterface with an execution screen of an application, wherein theapplication corresponds to the user input.
 18. The non-transitorycomputer-readable medium of claim 17, wherein replacing, when the userinput is the predefined input, the lock screen user interface with theexecution screen of the application comprises: bypassing an unlock userinterface, in response to a determination that the user input is thepredefined input; and displaying the execution screen of theapplication.
 19. The non-transitory computer-readable medium of claim17, wherein determining whether the user input is the predefined inputcomprises: verifying a user based on the detected user input through thetouch sensitive display; and concluding that the verification of theuser is successful based on a result of the verification of the userresult.
 20. The non-transitory computer-readable medium of claim 19,wherein verifying the user based on the detected user input through thetouch sensitive display comprises: extracting an input feature of thedetected user input through the touch sensitive display; comparing theinput feature with predefined verification information; and determiningwhether a verification of the user is successful based on a result ofthe comparison result.